An example of a fastener driving tool that drives a fastener into a workpiece by making use of the repulsive force of an elastic mechanism is described in Patent Document 1. The fastener driving tool described in Patent Document 1 includes an electric motor disposed inside a housing, an output shaft of the electric motor, a drum, a wire wound around the drum, an operating member to which the wire is connected, a blade attached to the operating member, a clutch mechanism that connects and disconnects the output shaft to and from the drum, a cylindrical spring guide disposed inside the housing, and a coil spring serving as an elastic mechanism disposed inside the spring guide and interposed between a partition wall of the housing and the operating member.
The clutch mechanism connects or disconnects a power transmission path for transmitting the torque of the electric motor to the drum. When the clutch mechanism connects the power transmission path and the torque of the electric motor is transmitted to the drum, the drum rotates in a forward direction to reel up the wire, causing the operating member to move toward the interior of the spring guide. When the operating member moves toward the interior of the spring guide, the coil spring is compressed, thereby accumulating elastic force.
Then, when the clutch mechanism disconnects the power transmission path, the drum rotates in a reverse direction due to the repulsive force of the coil spring, so that the wire is reeled out from the drum. As a result, the operating member moves toward the exterior of the spring guide, so that the fastener is struck by the blade to be driven into the workpiece.